Iron Onslaught now has the Steam leaderboard enabled and is accessible through the Community Hub. The leaderboard will show the amount of bots killed, mechs killed, how much credit you have, and the time you lived.
If one of your saves has more progress than your other save, it'll automatically update the leaderboard to the most progress you have (if you exit to main menu), and If you die, your progress will update to another save, but if you only have one save, your progress is set to 0.
And with the Steam leaderboard also comes some minor improvements to the enemies' core functionality, i.e., running to the player and looking at the player.